Why do some of my keys work fine in the door lock but others don't work at all?

If your door lock was re-keyed at the time of installation to match your interior door lock then the key that you provided to the technician is the key that should work. All other keys will only work if they were properly copied from the original key. You may have to return to your key maker and have the other keys re-done. Our technicians are not locksmiths and cannot make extra keys.